ROHD-692: only persist the most important subset of the cache to disk, because (de)serialization of large dicts is just too slow and memomy consuming

Task #11188: performance boost in writing cache to disk. Side effect: speeds up scheduling and webscheduler

Task #11090: keep results for unknown paths in cache as well, so we can return them quickly as well.

Task #9939: RA: CleanupService and StorageQueryService: fix resource selection by name from 'cep4' to 'CEP4' in accordance with changed CEP4 resource names in radb many commits earlier in this branch

Fix merge conflict on momqueryservice.py. Moved on trunk, but changed on this branch.
Solve by replacing the moved file with the changed file (thus, move the changed file over the moved file).
Careful checking of (JD's) changes shows this is correct; the changes are preserved.
Other moved files did not cause conflicts, since they were not changed.

Task #9351 #9353 #9355: let the cache be updated in the background only, yield cache results immediately in getDiskUsageForPath, even if they are old

Task #9351 #9353 #9355: added notifications on updates of diskusage for path. Handle notifications with datamanagementbuslistener (which was the cleanupbuslistener before).

Task #9351 #9353 #9355: added notifications on deletion of path/task. Handle notifications with cleanupbuslistener. Various fixes and improvements in cache